An electrosurgical pencil is a medical instrument which uses an electrode to apply a high-voltage, high-frequency electrical current to tissue to achieve a surgical effect, such as cutting of tissue and/or coagulation of blood oozing from the cut or lacerated tissue. During an electrosurgical procedure, applying the high-voltage, high-frequency electrical current to the tissue produces electrosurgical byproducts, which consist principally of smoke and which also include other debris. Because the smoke and debris may contain small amounts of pathogenic particles, inhalation by the surgical staff is undesirable and may present health concerns for the surgical staff. The smoke may also obstruct the surgeon's view of the surgical site and thus may impede progress in completing the electrosurgical procedure.
Smoke evacuators have been developed to remove the undesirable smoke and electrosurgical byproducts from the surgical site. A smoke evacuator includes a fan which develops a source of low pressure air which is conducted through a suction hose to the surgical site. The airflow created by the low-pressure source evacuates smoke and electrosurgical byproducts from the surgical site into an open end of the suction hose. The electrosurgical byproducts carried by the airflow are passed through a filter, which removes smoke, particulate debris and other electrosurgical byproducts, including odors, before the filtered air is discharged at a location remote from the surgical site but still within the surgical operating room.
While smoke evacuators are generally effective in removing the smoke and electrosurgical byproducts, using a smoke evacuator is accompanied by certain disadvantages. The open end of the suction hose must be maintained at the surgical site where the electrode delivers the high-voltage, high-frequency current to the tissue. A surgical staff person other than the surgeon must usually hold and manipulate the end of the suction hose while the surgeon manipulates the electrosurgical pencil during the medical procedure. In many types of medical procedures, the surgical site is not openly accessible and therefore it is impossible or difficult to place the open end of the suction hose adjacent to the surgical site while the surgeon is manipulating the electrode at the surgical site. Under such circumstances, some smoke or debris may escape evacuation. Placing the end of the suction hose at the surgical site may also obscure or limit the surgeon's view of the surgical site or make it difficult to manipulate the electrode in tight spaces caused by the presence of the end of the suction hose. Lastly, among other things, the suction hose, which extends within the operating room, and the smoke evacuator are additional pieces of equipment which must be dealt with in an already-congested operating room, thereby complicating the surgical procedure.
To avoid many of the physical complications and obstructions associated with a separate suction hose, a suction tube has been attached to the electrosurgical pencil with an open end of the suction tube located adjacent to the electrode. The suction hose from the fan low-pressure air source is connected to the electrosurgical pencil and to the suction tube. In this manner, the open end of the suction tube is always located adjacent to the electrode at the surgical site where the smoke and other electrosurgical byproducts are created. The suction tube is always maneuvered close to the surgical site as a consequence of manipulating the electrosurgical pencil during the procedure. A separate surgical staff person is not required to position the end of the suction hose, because the surgeon inherently maneuvers the end of the suction tube while manipulating the electrosurgical pencil. The suction tube evacuates the electrosurgical byproducts from the surgical site as those byproducts are produced.
Suction tubes have been combined with electrosurgical pencils in at least two different ways. One way involves creating an external clip-on shroud-like structure which connects to a standard electrosurgical pencil. A shroud is located adjacent to the electrode and contains its own flow passageway for evacuating the smoke and other electrosurgical byproducts. The shroud is connected by the suction hose to the low-pressure air source. Connecting the shroud to the electrosurgical pencil changes the size of the pencil and may make the electrosurgical pencil itself more awkward to hold and manipulate by the surgeon. The other way of combining a suction tube with an electrosurgical pencil is to integrate the suction tube as part of the structure of the electrosurgical pencil. In this circumstance, the suction tube is built into a handle or housing of the electrosurgical pencil. The integration of the suction tube with the pencil has the effect of eliminating the more bulky and somewhat awkward aspects of connecting a separate shroud to the electrosurgical pencil, and also eliminates the risk or possibility that the separate shroud will become disconnected from the pencil. However, manufacturing of the electrosurgical pencil is complicated as a result of integrating the suction tube and creating a flow passageway within the housing of the electrosurgical pencil for the evacuated smoke, debris and other electrosurgical byproducts.
One of the consequences of integrating the suction tube with the electrosurgical pencil is that the size of the suction tube may become relatively small. The size of a typical electrosurgical pencil simply will not accommodate a relatively large suction tube. Consequently, to be most effective in evacuating the electrosurgical byproducts, the open end of the suction tube must be positioned as close as possible to the surgical site and the electrode. A closely-located suction tube captures the airborne byproducts almost immediately after formation at the surgical site and before the byproducts can diffuse from the surgical site to an extent that effective evacuation becomes impossible.
One way of integrating the suction tube with the electrosurgical pencil is to position the entire suction tube laterally adjacent to the tip of the electrode. While this configuration is effective in some circumstances, the evacuation area adjacent to the end of the suction tube is laterally displaced from the tip of the electrode, thereby providing a greater opportunity for the electrosurgical byproducts to escape evacuation on the opposite lateral side of the electrode. In addition, having the suction tube extending laterally adjacent to the tip of the electrode may limit the ability of the surgeon to manipulate the electrode in close and confined surgical sites.
Electrosurgical pencils with a laterally positioned suction tube have also been constructed to permit selective extension or retraction of the suction tube. Selective extension or retraction of the suction tube allows the surgeon to position the open end of the suction tube close to the surgical site for more effective evacuation, or allows the end of the suction tube to be retracted from the tip of the electrode if the surgical site is confined or if the suction tube obscures the surgeon's vision of the surgical site. When the end of the suction tube is positioned further away from the tip of the electrode, the evacuation of the airborne electrosurgical byproducts is less effective and the electrosurgical byproducts are more likely to diffuse into the surrounding operating room environment without being captured.
A selectively extendable and retractable suction tube also more readily accommodates the use of different-length electrodes with the electrosurgical pencil. Depending upon the medical procedure or the state of the procedure, the surgeon may require the use of a longer electrode to extend the electrode to a surgical site. A variety of different length electrodes may be used during a single medical procedure, and in such circumstances, the ability to adjust the length and position of the suction tube relative to the tip of the electrode assures more effective evacuation of the electrosurgical byproducts than in those circumstances where the position of the suction tube cannot be adjusted relative to the tip of the electrode.
One way of integrating a somewhat larger suction tube in an electrosurgical pencil is to locate the electrode within the open end of the suction tube. Under such circumstances, the suction tube and the electrode occupy the same space within the electrosurgical pencil. Locating the electrode within the suction tube is relatively easily accomplished if the suction tube is fixed and not selectively extendable and retractable, because the socket or receptacle which receives and connects the electrode is in a fixed position relative to the suction tube. The fixed relative position eliminates the benefits of selective extension and retraction of the suction tube to achieve the most effective evacuation relative to different lengths of the electrode.
Instead of being fixed to the electrosurgical pencil housing, the suction tube may be made selectively extendable and retractable while maintaining the electrode within the open end of the suction tube. In this circumstance the electrode connection socket or receptacle is also fixed at or near the open end of the suction tube. The suction tube can be extended when it is desired to extend the tip of the electrode from the housing of the electrosurgical pencil itself. However, the open end of the suction tube is maintained in fixed relationship to the tip of the electrode, because the electrode moves in conjunction with the suction tube. The open end of the suction tube cannot be adjusted relative to the tip of the electrode to achieve the most effective evacuation. In a particularly confined surgical site, the extension of the suction tube may not be permitted because of space limitations. In such circumstances, a relatively long electrode may be used. Although the longer electrode can be substituted for a shorter electrode, the suction tube cannot be extended relative to the tip of the longer electrode because of the socket or receptacle for the electrode occupies a fixed position relative to the suction tube. The use of a longer electrode greatly diminishes the smoke evacuation efficiency because the tip of the electrode is spaced a greater distance from the open end of the suction tube.
It has been recognized that it would be desirable to locate the electrode within the interior of an extendable and retractable suction tube, to permit selective extension and retraction of the suction tube relative to electrodes of different length. However, retaining the electrode within the center of the suction tube while still permitting the suction tube to extend and retract relative to the stationary electrode is a complex matter.